Idolatry
by EndOfAbraxas
Summary: Late one night after being invited into Sachiko's bed, Yumi faces her biggest temptation, as well as a potential threat to the delicate relationship between them. A story about Yumi's neediness and Sachiko's nakedness. Yumi/Sachiko, with tiny hints of Yumi/Sei.


**Idolatry**

Slowly, steadily, like the tide of a calm ocean huffing its waters against the shore, Sachiko let out a long breath—and then drew it back in. Yumi watched in fascination as the small muscles near the top of Sachiko's ribcage stretched in the climax of each breath, as her pajamas danced around loosely over her skin.

The top few buttons of Sachiko's shirt had remained unfastened, and every time she dragged air softly into her lungs, more and more of her chest seemed to slip out of that very thin container.

At first, Yumi had only noticed a small shadow of skin underneath the silk; but as the shirt spread open further and her eyes adjusted to the moonlight, she could finally see the sides of Sachiko's breasts with increasing clarity. Near the top of one of those swells, the pale skin abruptly changed into a darker shade. It peeked out a little from edge of the cloth.

Yumi jerked her head down. She closed her eyes and smashed her face deep into the pillow beneath her.

 _Stop!_ a voice cried inside her head as her world was suddenly swallowed in darkness. _You can't look at Onee-sama like that! What are you thinking?_

Even though Sachiko was fast asleep, and there was no one else to witness her wandering gaze, Yumi still felt a burst of heat rising up to her face. _She trusts you enough to let you sleep in her room—in her bed—and you respond by staring at her like that?_

"Sorry," Yumi whispered against the pillow, though she wasn't sure to whom she was apologizing, or if they would ever hear her. To Maria-sama, perhaps?

The apology only served to make her feel like a hypocrite, though. Even as she repeated the word under her breath and kept her eyes tightly closed, the image of Sachiko's half-naked chest remained vividly in her mind's eye. She felt her heart pounding against her ribs.

 _What is this?_ Yumi thought.

But Yumi wasn't naive; she had found it pleasing to look at Sachiko's body, and she knew very well what _that_ meant, even if her brain was going there against her will. Long before, she had accepted that these feelings were normal—that she was human, after all, not one of the stone saints that decorated the Lillian University grounds back in Tokyo—but it was an entirely different story to indulge the feelings, to stare, to allow another person's nakedness to give her pleasure.

This was lust, probably. She couldn't be entirely certain. She wasn't sure how most people experienced it, but as she had grown older, some strange chemistry had awakened in her and she had begun to find those previously neutral shapes and lines on a person's body to be pleasing in a way that she felt a little guilty about.

Sometimes it was a man that she would find attractive, but most of the time it would be a woman. Oftentimes—to her embarrassment—it would be Sachiko.

In some ways, being attracted to Sachiko didn't bother her that much because usually there was no temptation to indulge it; she knew that acting on it was completely out of the question. There was very little longing when she couldn't even bring herself to fantasize. She could ignore the feelings most of the time.

The real problem was when an opportunity to indulge that chemical reaction would arise. She had done this the day before, when the other guest who was staying at Sachiko's summer home had snuck into Yumi's room in the middle of the night. She had been careful to not allow things to go too far—but perhaps she should have allowed it; perhaps that would have satiated her enough to save her from the insistent urge that she was facing now.

But no, touching Sachiko would be out of the question. Even just the thought of doing it—the fact that her brain was urging her at all—filled her with a special kind of shame.

In truth, she was probably being overly dramatic because she had traumatized herself a little earlier that evening. She had been reading some passages from the Bible for her theology class, flipping casually through the book of Colossians while sitting at the dining room table of Sachiko's summer home, when a few verses had jumped out at her:

 _Set your minds on things that are above, not on things that are on earth._

 _Put to death therefore what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry._

She had stared at the words for a long time, long enough to convince herself that God may have been personally chastising her for what she had been up to the night before in her room. This Bible was in English, and for some reason that had made the words appear more menacing and judgmental than usual—even if she hadn't understood all of them at first.

"What's _'idolatry'_?" she had mumbled to herself.

Satou Sei—who had been sitting across from her for most of the night—had laughed out loud and passed her a dictionary. "It's what you do every time you pray to the statue of Maria-sama," Sei had told her with a wicked smile.

Sachiko had looked up from her place at the head of the table and glared at Sei, but otherwise, neither of them said anything more about it.

Since this was hardly a good explanation, Yumi had cracked open the dictionary and flipped to the page in question. She had been surprised to find a large illustration accompanying the text. It was a photo of a stone icon that she indeed at first mistook for Maria-sama, but a blink or two later, she saw the naked breasts and the description underneath, and she had blushed a little at her assumption:

 _Hellenistic idol of Egyptian goddess Isis,_ the caption read.

Beside that, the definition:

 _idolatry (noun)_

 _1\. The worship of idols._

 _2\. The excessive admiration of somebody or something._

Sei-sama's dictionary had also been entirely in English, but Yumi had gotten the gist of the accusation it was making. _Excessive admiration?_ she had thought to herself. _Like_ akogare _?_

Like what she felt for…?

She had noticed then that the face of Isis looked a bit familiar. The feminine lines of the stone had oddly reminded her of Sachiko, even more than of Maria-sama. The three faces of the three goddesses seemed to have melted together suddenly in her mind.

The moment this thought had come to her, though, she had immediately snapped the dictionary closed.

And now, her eyes were similarly shut to the idol who was laying beside her in bed. She felt her breath puffing hard against the pillow, even as the fabric was already starting to suffocate her. As much as she tried to repress the thought, she knew that the urge she felt inside of her was not to bury her face in the silk lining of that pillow—but rather to bury her face against something more fleshly. The pillow was a poor substitute.

She felt her fingers digging into the sheets. When she couldn't hold her breath for a second longer, she finally turned her head and drank in a gulp of cold air. The sudden gasp that escaped her seemed to cause Sachiko to stir a little. Though Yumi's eyes were closed, she could hear some rustling, feel the coils of the bed vibrating with energy.

She opened her eyes with a bit of panic. By the time she looked, though, Sachiko had settled, her breathing as slow and deep and unconscious as before. Only now, the left side of her shirt had slid down off her shoulder. The coy flash of skin from before was no more.

Instead, one of Sachiko's breasts now hovered near Yumi's face.

"Ah—," Yumi huffed. She had to stifle what was very nearly a cry of surprise. She tried not to move. She tried not to look—but this, at least, was impossible. It felt like there were invisible strings attached to her eyes, tugging her gaze precisely where she was telling herself not to stare.

Sachiko's naked breast rose and fell rhythmically. Moonlight bathed the oblivious sleeper, and it gave her skin a milky glow, a soft look that made Yumi want to reach out and…

 _Oh God, what am I thinking?_

What was she _doing_ , more importantly? She couldn't just lie there and stare and leave her Onee-sama in an indecent state. If Sachiko were to wake up right then and there, she would surely be embarrassed, and Yumi didn't know if she'd be able to feign sleep quickly enough to save her Onee-sama some face.

But if she could just lift the side of that open shirt and gingerly pull it over to hide Sachiko's chest, then all would be well. She'd be able to preserve some of Sachiko-sama's dignity, as well as her own sanity; she'd be able to pretend that none of this had happened.

Carefully, her eyes flicking quickly towards Sachiko's sleeping face as she moved, Yumi wrested her arm from beneath the covers. Once or twice, she stopped abruptly when Sachiko's breathing seemed to change, but soon enough she realized that it was probably her imagination more than anything.

When her hand finally emerged from under the sheets, she brought it up to the edge of Sachiko's shirt. Even as her fingers lightly grasped the fabric, Yumi could feel the heat radiating up from Sachiko's flesh and warmly hitting her hand. Sachiko breathed in deeply, and her chest expanded, and the tip of her breast nearly grazed Yumi's skin, but Yumi tried with all of her moral strength not to allow the touch to happen.

She held her breath. She slowly began to tug on the edge of the shirt flap, lifting it up as best she could with her thumb and forefinger, tightening her delicate grip when she realized that the silk of the pajamas was a bit more slippery than she had assumed.

It was too late, though. She had been too careful, too light in her movements. The fabric slipped through her fingers and landed just at the base of Sachiko's breast, draping the bottom with an almost decorative flare.

Yumi would have gasped in frustration if she wasn't overly cautious of the noise. Even her heart pounding in her ears made her paranoid that Sachiko would hear.

But then she sensed it. From the corner of her eye, she felt the sudden shine of what seemed like a pair of small mirrors. This was accompanied by a sharp intake of conscious breath. Yumi froze at first, but soon enough she forced her gaze up towards the sleeper's face.

Sachiko stared back down at her.

Onee-sama's eyes were sleepy, but there was no question that she was awake, and underneath that drowsy gaze there was a definite edge of curiosity. Her gaze moved lazily at first, from Yumi's face, down to Yumi's still hovering hand, and finally to what was underneath it. A bit of surprise soon replaced the question on her face.

"Yumi…?" she whispered. Her voice sounded half-asleep, but her eyes were slowly opening further.

"Onee-sama, I—," Yumi began in a low voice, but she stopped. She knew quite well what this might have looked like from Sachiko's perspective. Even now, her hand was still hanging stupidly over Sachiko's exposed breast.

Yumi quickly pulled her hand away. She swallowed hard and found that she couldn't say anything more when she realized that Sachiko was staring at her intensely. The gaze was hard and serious, with no sign of conflict or thought; it was that blank face that Yumi had always feared the most. It was the face that could harbor all levels judgment, and Yumi was helpless against it.

Suddenly—and completely against her will—Yumi felt her eyes growing warm with nervous tears. "Onee-sama," she whispered in a pleading voice, "it's not—"

But then her voice cut out. It was muffled all of a sudden. Her eyes automatically closed just as they had when she had forced her face against the fabric of her pillow, only now her face was instead pressed tightly against much warmer flesh, and when she inhaled deeply, she could swallow the unmistakable scent of her Onee-sama's skin. She felt an arm wrapped around her, a hand gently guiding her head to its place against Sachiko's chest—and before she could even understand what was happening, Sachiko had fully embraced her.

The tears that had been edging finally spilled over. She couldn't hold back, and she sobbed into Sachiko's bosom, her breaths flowing through her like small shudders. It was like the container where she had repressed everything for the entire night—or maybe even for the entire week, or maybe even for years—had finally cracked the moment Sachiko touched her, and all the tension inside of her had burst from her body all at once.

" _Yumi?_ " There was alarm in Sachiko's voice. "Yumi, what on Earth is the matter?"

The crying ended within seconds; the release had been so quick, it was nearly unsatisfying, and Yumi was left quietly sniffling, wincing as the warm water oozed down her cheek and against Sachiko's skin. She was left a bit embarrassed in its wake. Luckily, she couldn't see Sachiko; her face remained buried in her Onee-sama's chest.

It finally struck her that Sachiko hadn't noticed anything—or else, she hadn't cared that Yumi seemed to have been trying to touch her. Just as any other time they had come together, Sachiko had pulled Yumi towards her with affection, with no sign of judgment. The very breast that Yumi had coveted and agonized over only moments before, was now pressed against her face shamelessly.

Sachiko obviously thought nothing of it. It was Yumi who had colored the whole situation in shame. Being faced with Sachiko's innocent perspective only served to make Yumi feel even more guilty.

What had she been thinking? This whole time, she had been fearful of God's judgment or of Sachiko's judgment, but the problem had really been within herself. What kind of _imouto_ was she? How could she have taken something so pure as the touch of her Onee-sama's body and viewed it through the lens of sensuality, and turned it into something to be ashamed of?

The touch wasn't the problem. The breast wasn't the problem. It was that Yumi had allowed herself to—

Yumi noticed suddenly that Sachiko had moved. It was a slight shift, but Sachiko had adjusted her body and Yumi felt the hand that was pressing against the back of her head guiding her with a bit more insistence. Yumi allowed it. She relaxed and found that her face slid a bit against Sachiko. She opened her eyes with curiosity when she felt a new texture brush lightly against her lips.

Her body stiffened once again. Her lips had fallen against the very tip of Sachiko's breast. She was too stunned to pull away even on reflex at first, to correct the obvious mistake. Once she had come to her senses a little, she began to turn away, but once again she felt the guiding hand gently pressing where the back of her skull met her spine, gently pulling her closer.

Her gaze wandered down for a moment when she saw some movement. In the dim moonlight, she noticed a few slender fingers wrapped along the base of that pillow of flesh. It took her a moment to realize that Sachiko was holding it up with her other hand.

She was offering it to Yumi.

Because she couldn't believe it at first, Yumi's gaze quickly flickered up to Sachiko's face. As before, though, her Onee-sama's expression was mostly neutral. Only a small edge of expectation was present; she was waiting. She was holding up the very thing that Yumi had gazed at with shame, and she was waiting.

There was no way that this was Sachiko's intention, though, Yumi thought. Perhaps it appeared this way, but it had to be something else. Yumi was obviously misinterpreting this somehow, maybe because it was precisely something that she had longed for. Her own lust and wanting had clouded her ability to perceive Sachiko's real intention. There was simply no way that Sachiko was encouraging Yumi to…

" _Open,_ " Sachiko whispered. Her voice was insistent.

Every nerve in Yumi's body felt very suddenly alive, vibrating with what seemed like a shock of electric energy.

 _Oh God. This can't be real_ , she thought. On some level, the feeling was pleasing, but on another level it filled her with fear. A million thoughts flooded her mind, a million reasons to pull back.

Then Sachiko nudged Yumi softly again—and once again, Yumi's lips brushed against the place that she had been both avoiding and craving, the spring that she had been forcing herself not to drink from.

The thoughts stopped. She opened her mouth—in obedience and reverence to Sachiko's gentle demand more than anything—and she felt the contrasting textures of both smooth and slightly rougher skin passing between her lips.

Entirely on instinct, she latched on, inhaled the skin into her mouth. It felt strangely natural, like she had done it before, like she had been doing it every day.

Sachiko immediately gasped. She pressed harder against the back of Yumi's head, brought her closer. Without thinking, Yumi swallowed more, tasted the flesh more deliberately with her tongue, allowed her hands to slide and roam around the rest of Sachiko's chest. It was like she was grasping for something, trying to get closer, trying to draw something out of Sachiko's body and into her own.

When she dared to look up at Sachiko's face once again, she was shocked to see that the older woman wasn't trying to hide her reaction. Her face was tinted with a blush, her eyes looked dreamy with pleasure. She watched Yumi openly, with a vulnerability that made it difficult for Yumi to stare back.

Somehow, she still did, though. They laid there together for a long time, their eyes locked. Sachiko caressed Yumi's face in quiet encouragement, even as her breaths came out raggedly. Yumi could feel her Onee-sama's roaring pulse against her lips.

The longer they remained together, though, the more the tension smoothed out. Before long, their breathing had come into sync, like they had melted into a single body, and Yumi found that she naturally had stopped moving, had grown slack.

Eventually, without giving it any thought, simply as another reflex, she released Sachiko and her body pulled back on its own. She sucked in a hard breath the moment her mouth was once again empty.

She felt Sachiko shudder. Yumi looked at the breast that remained near her own face and noticed that it looked a bit different now, a bit swollen, with a tinge of pink that hadn't been there before.

When Sachiko pulled away, she rolled heavily onto her back and relaxed with her gaze facing the ceiling. Her shirt had fallen open so that her entire chest now lay exposed in the moonlight. There was no shame on her face. There was nothing.

Yumi had no idea what to say. "Onee-sama…," she whispered after a moment, when she couldn't hold back anymore from breaking the silence that was quickly filling the room.

" _Shhhhh_ ," Sachiko immediately responded. The message was firm, but oddly soothing.

What seemed like a long time passed. They faced the silence together, and after awhile Yumi let go of the discomfort that came with it.

Then, just as Sachiko was closing her eyes and Yumi was certain that she was going back to sleep, she let out a long sigh. "Yumi…," she said. There was a pause, as if a thought had come, but the words yet hadn't. Then she murmured, her eyes still closed, "I am aware that Sei-sama visited your room late last night."

Yumi stared at her, stunned. Out of all the things Sachiko could have said, Yumi hadn't expected this random confession that seemed wholly unrelated to what they had just done. She tensed up in embarrassed surprise. When she could finally muster up the ability to move again, her mouth managed to form some words: "How did you…?"

She had been so careful that night to keep as quiet as she could; she had kept her footsteps light as Sei had chased her around; she had tried to suppress her giggles as they playfully fought. She had been so positive at the time that no one else in the house had been the wiser.

Sachiko smiled and turned to look at her. "You're my _soeur_ , aren't you? I'd like to think I've developed a sixth sense by now when it comes to you."

Yumi averted her gaze. On one level, what she had done with Sei had been nothing to be ashamed of. They had merely played a little as they usually did, had merely embraced a few times in the dark. When Sei's touch had traveled to the less innocent places, it had merely been a light graze and nothing more. Yumi had even pushed Sei away when she tried to kiss her, and after a few more attempts, Sei had taken the hint and disappeared with her usual unaffected smirk.

But of course, it wasn't about what they had physically done. It was about the fact that Yumi had _enjoyed_ it. Part of the temptation had been that she rarely found herself alone with Sei-sama anymore, and Sei had only been able to visit Sachiko's summer home for two nights. Yumi knew that she would lose her senpai to a flood of schoolwork as soon as they were all back in Tokyo, so maybe part of her had wanted to indulge her a little while the rare opportunity was there.

Then it finally clicked in Yumi's mind. She abruptly understood why she had even ended up in Sachiko's room in the first place.

"Onee-sama asked me to sleep in her room tonight because she wanted to protect me from Sei-sama?" Yumi said aloud.

Sachiko nodded.

Yumi wasn't entirely sure that Sachiko grasped the irony of what had just happened. She searched her Onee-sama's face, but there was no shame. Sachiko had been trying to keep her from being corrupted by an overly-affectionate senpai, and yet only moments before, she and Sachiko had ended up…

It occurred to Yumi then that, again, maybe Sachiko was viewing this through an entirely different lens. Perhaps Sachiko had thought nothing of what they had just done. Perhaps she had merely noticed what Yumi wanted to do, and had allowed it without realizing any of the sexual overtones that Yumi had attached to it. Perhaps Yumi was alone in the way that she privately worshiped Sachiko, in the way that her admiration so naturally seemed to transform into lust.

No, not lust. _Idolatry_.

The same way that she prayed to Maria-sama, imploring her every day for good fortune, clasping to her for motherly guidance, drawing from her some kind of life-force, she had clasped herself against Sachiko and sucked on her breast until that burning _want_ inside of her had been indulged.

She had no idea how to feel about it. She was supremely confused, and Sachiko's now seemingly indifferent demeanor didn't help. Worst of all, she wasn't satisfied. Her body ached for something more, something she didn't dare visualize.

All of a sudden, Sachiko turned to her. She laid a hand softly on Yumi's cheek. As Sachiko moved, her face fell into a patch of bright moonlight, and Yumi's image of her grew clearer. There was a blush on her face again; it was growing deeper, into a rose-colored shade that Yumi had only seen in Sachiko's expression a few times before.

She didn't notice at first that Sachiko was moving down towards her until she felt that steady breath hitting her face. Yumi tilted her head up with curiosity and Sachiko kissed her lightly on the lips with no hesitation.

Yumi stiffened in surprise. Before long, though, she felt herself relaxing, felt herself surrendering to how strangely natural it all felt.

They had done this before—once. But it was different this time; Sachiko's mouth was slightly open, and Yumi could taste Sachiko's scent in a way she had never been able to before. They kissed for a long moment, Yumi stretching up to meet the touch, as if she were receiving some kind of transfer of energy, some kind of message.

When Sachiko finally broke away, she looked directly at Yumi. "Whenever you would like...," she said, "I'm here."

And that was all she said.

Seconds later, after Yumi had the chance to only blink a few times in confusion, Sachiko had turned back over to her side of the bed and closed her eyes. As the moments passed, her breathing deepened again, her muscles seemed to slacken, and Yumi was sure that she had somehow drifted quickly off to sleep, in spite of all that had occurred between them.

Yumi couldn't sleep. She merely laid there and stared at the reclining woman beside her, the woman who suddenly appeared much less statuesque than before. Her skin seemed less pale for some reason, less like stone, even though the light had hardly changed.

The touch had altered Yumi's perception. Something had changed in the lens that she used to see Sachiko. She had just kissed those very real, very warm lips, and had just fondled previously untouchable places. She had reached out towards that idol, and it had transformed into warm flesh before her eyes.

Yumi had never been so terrified in her entire life.

* * *

 _A/N:_

 _Yes, this story was just an excuse to write a bunch of stuff about Sachiko's boobs. There is actually a lot of sexual / fertility imagery in Marimite, if you look for it, so I wanted to pay homage to it._

 _Seriously, though, for some reason this past week I started thinking about how Yumi's relationship with Sachiko has a very subtle sexual element to it, but that this element is tinged with an almost incestuous feel; not because they have a "sisterly" relationship, but actually rather because Sachiko is so much of a mother figure to Yumi. She is very much like an incarnation of Maria-sama from Yumi's perspective at first, before Yumi really gets to know her, and even to an extent after they grow closer._

 _I could see Yumi having a very Freudian response to this, so I became obsessed with the idea of how Yumi would physically express this style of attraction. Then I wrote this story._

 _But mostly, I wanted to write about boobs._

 _Leave a comment if you want, especially if it's about boobs._

 _Boobs._

 _* Bible verses are from Collosians 3:2 and 3:5, if you were curious._


End file.
